1. Field of the Invention
The present invention relates to a weighing system, a packing system and a weighing and packing system, and more particularly to a weighing system, a packing system and a weighing and packing system in which a weighing driving section of each of a plurality of weighing units, a weighing control section for controlling the weighing driving section, a packing driving section of a packer, a packing control section for controlling the packing driving section and the like are coupled through a LAN.
2. Description of the Related Art
Conventionally, a combination scale has been combined with a packer to form a weighing and packing system to be used. FIG. 13 shows a weighing and packing system according to the prior art. The weighing and packing system comprises a scale driving section 182 for driving a combination scale body 183, and a weighing control section 181 for controlling the scale driving section 182. The weighing control section 181 is connected to a SIO (serial interface) 199a of a control indicating section 198 through a SIO 190a. Weighing data and the like sent from the combination scale body 183 is converted to digital information by an A/D converter 184, and the digital information is transmitted to the control indicating section 198 through the SIO 190a.
The weighing and packing system comprises a packing driving section 187 for driving a packer body 188, and a packing control section 186 for controlling the packing driving section 187. The packing control section 186 is connected to a SIO 199b of the control indicating section 198 through a SIO 190b. Temperature information and the like sent from the packer body 188 is converted to digital information by an A/D converter 189, and the digital information is transmitted to the control indicating section 198 through the SIO 190b.
The control indicating section 198 includes a microcomputer 197, an operation input section 191, a display section 192, and the SIOs 199a and 199b. Furthermore, the microcomputer 197 has a key input register 193, an operating condition table 194, an operation state register 195, a display buffer 196 and the like.
In the weighing and packing system, control information is sent from the microcomputer 197 to the weighing control section 181 in response to input from the operation input section 191. The weighing control section 181 controls the scale driving section 182 on the basis of the control information so that the combination scale body 183 is caused to operate. Data such as a weighed value sent from the combination scale body 183 is converted to a digital value by the A/D converter 184, and the digital value is sent to the control indicating section 198 and is displayed by the display section 192. In a packer control section 190, the packing driving section 187 is controlled according to an instruction sent from the control indicating section 198 so as to pack articles to be weighed which are fed from the combination scale body 183. Data obtained from the packer, for example, a seal temperature or the like, is converted to a digital value by the A/D converter 189, and the digital value is sent to the control indicating section 198 and is displayed by the display section 192. Thus, in the weighing and packing system, combination weighing and packing operation is performed under unified control of the control indicating section 198.
In the system shown in FIG. 13, however, data are transferred through the SIOs 190a, 190b, 199a and 199b, and a transmission line formed by a serial line. For this reason, there is a problem that the system has poor quick response to the control information and the like sent from the combination scale body 183 to the packer body 188 after completion of weighing operation. In addition, if abnormalities are caused on the combination scale body 183 or the packer body 188, it is impossible to rapidly halt the weighing and packing operation. Furthermore, if abnormalities are caused on transmission lines connecting the SIOs 190a and 199a and the SIOs 190b and 199b, the weighing and packing operation should be halted.
In the prior art system shown in FIG. 13, if the weighing units forming the combination scale are to be exchanged or added, the operation should be stopped. As a result, the operational efficiency of the system is lowered. Also in the packer body, if a section forming the packer body, for example, a sensor for a seal temperature is to be added, hardware of the packer control section 190 should be changed correspondingly.